1. Field of the Invention
The present invention relates to an information processing apparatus and a communication function expansion method.
2. Description of the Related Art
In recent years, the use of mobile telephones is spread widely and, at the same time, the main bodies of mobile telephones are made increasingly smaller in size. On the other hand, the demand for realizing a mobile telephone serving as an information processing apparatus having more advanced functions have risen.
To satisfy such a demand, there is proposed expanding the function of a mobile telephone using an external input/output interface (I/F). To be specific, a wire or radio connection interface is provided in a mobile telephone and an external apparatus is connected to the mobile telephone through this interface. For example, Jpn. Pat. Appln. KOKAI Publication No. 9-149107 discloses a mobile telephone having an external terminal for connecting a headset to the mobile telephone. If a headset plug is inserted into the external terminal, in particular, the microphone and the speaker of the mobile telephone are switched over to the microphone and the speaker of the headset.
In addition, Jpn. Pat. Appln. KOKAI Publication No. 8-234931 discloses a switching control circuit for a personal computer which is an information processing apparatus, wherein when a PCMCIA-compatible card is connected to the personal computer, the switching control circuit selects one of the connection of a card connection port with a system bus and the connection of the card connection port with a moving picture dedicated bus in accordance with the function of the card.
However, no consideration has been given to providing a radio external input/output interface on a mobile telephone or personal computer.
Furthermore, no matter which apparatus is connected to the external input/output interface of the mobile telephone, communication between the mobile telephone and an external unit is held only through a public line and other media cannot be used for the communication therebetween. Thus, the expandability of the conventional mobile telephone is insufficient.